PITTSBURGH — A former armored car guard has been sentenced to life in prison plus 10 to 20 years in the murder of his partner as part of what prosecutors said was a plot to steal $2.3 million from their truck. Twenty-four-year-old Kenneth Konias Jr. of Dravosburg was sentenced today. An Allegheny County judge convicted Konias in November of first-degree murder, robbery and theft. The judge found that Konias killed fellow Garda Cash Logistics guard Michael Haines and stole the money they had collected from businesses earlier that day, Feb. 28, 2012, most of it from Pittsburgh’s Rivers Casino. Haines’ body was found inside the idling truck under Pittsburgh’s 31st Street Bridge.